To find out which journals and publishers grant advanced permission for 'green', i.e. gratis, open access, see the SHERPA RoMEO database and its statistics page.

In addition to 'green' open access, more and more publishers are experimenting with 'gold' open access. SHERPA currently lists 92 publishers offering hybrid OA options, including all of the largest scholarly publishers.

Not sure what the colours mean? There is an explanation.

For more details on Open Access, go to the UQ Library's Open Access site.